September should have been a busy month for US IPOs. Instead, only four operating companies debuted (excluding SPACs), several pulled their offerings, and the two largest AI labs both reportedly pushed their timelines back. The Nasdaq hit record highs over the same period, so this isn't a market-wide sell-off. It's a public market being selective about price, disclosure and timing.

Why "Public" and "Private" Are the Wrong Categories for Thinking About Access to Cash Bending Spoons went public on Nasdaq on July 1, and the market did not wait around to make up its mind. Shares priced at $29, opened strong, and closed the first day up nearly 40%, valuing the Milan-based acquirer of AOL, Vimeo, Eventbrite, and a dozen other formerly-left-for-dead internet brands at roughly $25 billion.

This year, the bell finally rang for SpaceX. Its listing became one of the largest public debuts on record, and Anthropic and OpenAI are now taking their own steps toward the public markets. Taken together, these companies could introduce more than $3 trillion of new market value to public investors in a matter of months, representing a concentration of value entering the public markets in a single window that has few precedents.

A lockup is a contractual restriction, negotiated between the company and its underwriters, that prevents insiders, employees, and pre-IPO investors from selling shares for a set period after listing. Standard terms run 90 to 180 days, though the exact length and who it applies to varies by deal.

SpaceX prices its IPO Thursday, with first trades Friday on the Nasdaq under ticker SPCX, at a fixed $135 per share. The base raise is $75 billion, rising toward $86 billion if underwriters exercise the over-allotment, the largest offering in history by a wide margin. In the same stretch, Anthropic and OpenAI each confidentially filed draft S-1 paperwork with the SEC. Anthropic filed first, on the heels of a funding round valuing the company near $965 billion. OpenAI followed

On May 11, 2026 SpaceX filed its initial Form S-1, and on June 3 the company filed an amended S-1/A that, unusually, set an exact offering price rather than a range: 555,555,555 Class A shares at $135.00, raising approximately $75 billion at a $1.77 trillion fully diluted valuation. Shares are expected to begin trading on Nasdaq under the ticker SPCX later this month, per press reports. The size is unprecedented — the largest IPO in U.S. history, twice the prior record.

In December 2024, Bloomberg reported a secondary share sale that valued the company at about $350 billion. Separately, Reuters reported in late 2025 that SpaceX was exploring an IPO that could raise more than $25 billion and value the company at over $1 trillion. Even taking the more conservative $350 billion figure, SpaceX would arrive at the public markets as one of the largest companies ever to list.bThat is what makes a potential SpaceX IPO so different.

When we last wrote about Cerebras, the company had confidentially refiled for IPO and the debate was theoretical: would public markets reward a capital-intensive AI infrastructure company on strategic positioning alone, as longtime backer Coatue argued, or would “price matter” once a real-time pricing engine got involved?

This week The Information reported that Cerebras Systems, the Silicon Valley chip designer built around its wafer-scale computing architecture, has confidentially refiled for a U.S. IPO that could come as soon as April 2026.

The IPO market is technically open…but it’s already becoming choosy. A week ago, Blackstone’s president declared that “2026 should be the year of the IPO.” Just days later, one of Blackstone’s own portfolio companies put that assumption to question. On the surface, it was a busy week for new listings, with seven IPOs and six SPACs pricing. But it was also notable for what didn’t happen.